#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define rep(i, a, b) for (int i = (a); i <= (b); i++)
#define per(i, a, b) for (int i = (a); i >= (b); i--)
#define endl '\n'
const int N = 1005;

int n, m;
int a[N];
ll sum[N];
double v;
void solve(int id) {
  n *= m;
  rep(i, 1, n) cin >> a[i];
  cin >> v;

  sort(a + 1, a + n + 1);
  rep(i, 1, n) sum[i] = sum[i - 1] + a[i];
  rep(i, 1, n) {
    // a[i] < h <= a[i + 1]
    // v = 100 * i * h - sum[i]
    // v + sum[i] = 100 * i * h <= 100 * i * a[i + 1]
    double x = v + 100.0 * sum[i];
    if (i + 1 <= n && 100.0 * i * a[i + 1] < x) continue;
    double h = x / (100.0 * i);
    double p = i * 100.0 / n;
    cout << "Region " << id << endl;
    cout << "Water level is ";
    cout << fixed << setprecision(2) << h;
    cout << " meters." << endl;
    cout << fixed << setprecision(2) << p;
    cout << " percent of the region is under water." << endl;
    cout << endl;
    return;
  }
}
int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  // freopen("1.txt", "r", stdin);
  // freopen("2.txt", "w", stdout);
  int id = 0;
  while (cin >> n >> m && n != 0 && m != 0) {
    solve(++id);
  }
  return 0;
}